Zig Panic Recover

Recover calls a function and regains control of the calling thread when the function panics or behaves undefined. Recover is licensed under the terms of the MIT License.

How to use

Recover call, calls function with args, if the function does not panic, will return the called function's return value. If the function panics, will return the provided error.Value.

const recover = @import("recover");

try recover.call(function, args, error.Value);

Example

Returns error.Panic because function division panics with runtime error "division by zero".

fn division(num: u32, den: u32) u32 {
    return num / den;
}

try recover.call(division, .{1, 0}, error.Panic);

Prerequisites

• Enabled runtime safety checks, such as unreachable, index out of bounds, overflow, division by zero, incorrect pointer alignment, etc.

• In the root source file override the default panic handler and call recover panicked.

pub fn panic(msg: []const u8, error_return_trace: ?*std.builtin.StackTrace, ret_addr: ?usize) noreturn {
    recover.panicked();
    std.builtin.default_panic(msg, error_return_trace, ret_addr);
}

• Excluding Windows, linking to C standard library is required.

Proper Usage

• Proper use of recover is only for testing panic and undefined behavior runtime safety checks.
• It is not recommended to use recover as a general exception mechanism.